Method of correction between electrical phase angle and mechanical output angle of stepper motor
US5847475A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 1996 |
| Grant date | Dec 8, 1998 |
| Priority date | — |
| Expiry date | Jul 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/41326
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention describes a method that makes it possible to correct a nonlinear relationship between the electrical phase angle and the mechanical output angle of stepper motors, using a low-resolution encoder or the like. The method of the invention makes a compromise between the conventional closed-loop control of stepper motors, which requires high resolution of angular detection, and a purely static correction of the characteristic curve. The result is a substantial improvement in synchronization, for instance when conventional claw pole stepper motors are used, as a pointer drive for a gauge in a motor vehicle. The microstep triggering is done with a corrected sinusoidal form; for the correction, coefficients that are evaluated by means of a simplified Fourier synthesis are essentially used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.